Chronic Kidney Disease and the Risk of Incident Gout Among Middle-Aged Men: A Seven-Year Prospective Observational Study

Authors

  • Eswar Krishnan

    Corresponding author
    1. Stanford University School of Medicine, Stanford, California
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    • Dr. Krishnan has received consulting fees, speaking fees, and/or honoraria from URL Pharma, Metabolex, and Ardea Biosciences (less than $10,000 each) and Takeda (more than $10,000).


  • ClinicalTrials.gov identifier: NCT 00000487.

  • This study was performed using a limited-access data set obtained from the National Heart, Lung, and Blood Institute (NHLBI) and does not necessarily reflect the opinions or views of the Multiple Risk Factor Intervention Trial (MRFIT) or the NHLBI.

Abstract

Objective

The kidney is the major organ that facilitates excretion of urate in humans. Surprisingly, few studies have assessed whether a reduced glomerular filtration rate (GFR) and/or kidney damage is associated with a higher incidence of gout, and this study was undertaken to address this question.

Methods

Data from a 7-year followup of patients enrolled in the Multiple Risk Factor Intervention Trial, a primary prevention trial for cardiovascular disease among 12,866 men ages 35–57 years, were used for the present investigation. Presence of gout was determined by the study physicians from the original trial. Chronic kidney disease was defined using criteria similar to those proposed by the National Kidney Foundation. The Cox proportional hazards regression model was used to assess the association between gout and chronic kidney disease, after accounting for the effects of potential confounders.

Results

Overall, there were 722 cases of physician- diagnosed incident gout over 76,602 person-years of followup. The standardized incidence ratio of gout among those with chronic kidney disease was 1,217 (95% confidence interval [95% CI] 1,191–1,244). The adjusted hazard ratio (HR) among those with chronic kidney disease was 1.61 (95% CI 1.60–1.61). Each standard deviation decline in the estimated GFR was associated with an HR of 1.43 (95% CI 1.35–1.51). Including the serum urate level, as well as the urate–chronic kidney disease interaction term, as variables in the second analysis did not attenuate the HR. Proteinuria and hematuria, two markers of kidney damage, were associated with an elevated risk of gout independent of the estimated GFR.

Conclusion

Chronic kidney disease manifesting as reduced glomerular function or as presence of blood or protein in the urine increases the risk of incident gout.

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